Waht every you have in:
/includes/modules/payment

needs to have a match in:
/includes/languages/english/modules/payment

And, you need to make sure that the code files are in:
/includes/modules/payment

and the language files are in:
/includes/languages/english/modules/payment

What info shows up in your debug logs I am assuming you looked in /logs and refreshed your FTP program for the most recent?